rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7477/1:b..l P10725/1:b..l
rcu: (detected by 1, t=10502 jiffies, g=48877, q=199 ncpus=2)
task:syz.2.1087 state:R running task stack:23000 pid:10725 tgid:10725 ppid:5834 task_flags:0x40064c flags:0x00080003
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7078
preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
__raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
_raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:392 [inline]
zap_pte_range mm/memory.c:1884 [inline]
zap_pmd_range mm/memory.c:1946 [inline]
zap_pud_range mm/memory.c:1975 [inline]
zap_p4d_range mm/memory.c:1996 [inline]
unmap_page_range+0x38be/0x4170 mm/memory.c:2017
unmap_single_vma mm/memory.c:2059 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2101
exit_mmap+0x239/0xb10 mm/mmap.c:1277
__mmput+0x118/0x430 kernel/fork.c:1173
exit_mm+0x169/0x230 kernel/exit.c:581
do_exit+0x627/0x22f0 kernel/exit.c:959
do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
get_signal+0x1285/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
irqentry_exit+0x178/0x670 kernel/entry/common.c:196
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f7e52f8f751
RSP: 002b:fffffffffffffe70 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f7e531e6270 RCX: 00007f7e52f8f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f7e53013f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f7e531e6308 R14: 00007f7e531e6270 R15: 00007ffe9c07a948
task:udevd state:R running task stack:23488 pid:7477 tgid:7477 ppid:5192 task_flags:0x400140 flags:0x00080800
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7221
irqentry_exit+0x5e3/0x670 kernel/entry/common.c:216
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:arch_test_and_set_bit arch/x86/include/asm/bitops.h:136 [inline]
RIP: 0010:arch_test_and_set_bit_lock arch/x86/include/asm/bitops.h:142 [inline]
RIP: 0010:test_and_set_bit_lock include/asm-generic/bitops/instrumented-lock.h:58 [inline]
RIP: 0010:folio_trylock include/linux/pagemap.h:1133 [inline]
RIP: 0010:find_lock_entries+0x6ba/0xa60 mm/filemap.c:2179
Code: ff 49 83 e6 01 48 8b 5c 24 28 0f 85 73 03 00 00 4c 8b 74 24 18 4c 89 f7 be 08 00 00 00 e8 ee ad 2d 00 31 f6 f0 49 0f ba 2e 00 <41> 0f 93 c6 40 0f 92 c6 bf 02 00 00 00 e8 64 dd c6 ff 45 84 f6 75
RSP: 0018:ffffc90003cff500 EFLAGS: 00000246
RAX: ffffffff81f9e001 RBX: ffffc90003cff9a0 RCX: ffffffff81f9e042
RDX: 0000000000000001 RSI: 0000000000000000 RDI: ffffea0001120c40
RBP: ffffc90003cff650 R08: ffffea0001120c47 R09: 1ffffd4000224188
R10: dffffc0000000000 R11: fffff94000224189 R12: ffffea0001120c40
R13: 0000000000000c02 R14: ffffea0001120c40 R15: 0000000000000001
shmem_undo_range+0x254/0x1490 mm/shmem.c:1119
shmem_truncate_range mm/shmem.c:1249 [inline]
shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379
evict+0x5f4/0xae0 fs/inode.c:837
__dentry_kill+0x209/0x660 fs/dcache.c:670
finish_dput+0xc9/0x480 fs/dcache.c:879
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
exit_to_user_mode_loop+0xef/0x4e0 kernel/entry/common.c:75
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
do_syscall_64+0x2c1/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4b48bc9407
RSP: 002b:00007ffe22d1c540 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007f4b48b3d880 RCX: 00007f4b48bc9407
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007f4b48b3d6e8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002
R13: 000056208d43f410 R14: 0000000000000008 R15: 000056208d44bfe0
rcu: rcu_preempt kthread starved for 10562 jiffies! g48877 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt state:R running task stack:27416 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5282 [inline]
__schedule+0x14ed/0x5040 kernel/sched/core.c:6894
__schedule_loop kernel/sched/core.c:6976 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6991
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
rcu_gp_fqs_loop+0x301/0x11b0 kernel/rcu/tree.c:2095
rcu_gp_kthread+0x9b/0x2d0 kernel/rcu/tree.c:2297
kthread+0x389/0x480 kernel/kthread.c:467
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 be 2a 00 f3 0f 1e fa fb f4 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffffff8de07dc0 EFLAGS: 000002c2
RAX: 000000000069325b RBX: ffffffff8197161e RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d9a0b7f RDI: ffffffff8be08c60
RBP: ffffffff8de07eb0 R08: ffff8880b863375b R09: 1ffff110170c66eb
R10: dffffc0000000000 R11: ffffed10170c66ec R12: ffffffff8fa25d70
R13: 1ffffffff1bd29b8 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c07000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000006a73a000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x73/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:191 [inline]
do_idle+0x1be/0x4d0 kernel/sched/idle.c:332
cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:430
rest_init+0x2de/0x300 init/main.c:757
start_kernel+0x386/0x3d0 init/main.c:1207
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x143/0x1c0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x147